We will develop an ink-jet based micro-dispensing system with integrated liquid chromatography capability. This system will be used to prepare matrix- assisted laser desorption/ionization (MALDI) mass spectrometry targets for use in proteomic analysis. MicroFab's high-speed "printer" will deposit multiple spots from a digested protein sample onto a metal plate. Each spot in the array will essentially be the fraction collection vessel for peptide mapping. The metal plate will be put directly into the MALDI mass spectrometer for analysis. Since the fractions are put directly onto the MALDI grid, analysis is as sensitive as liquid chromatography-mass spectrometry (LC/MS) without sacrificing the high- throughput characteristic of MALDI. In Phase I we will demonstrate the proof of principle by dispensing peptide microspots with a MicroFab dispensing device with integrated reversed-phase resin microcolumn, selecting a MS matrix for good crystal formation, and determining the sensitivity of the system. In Phase II we will build a prototype printer capable of producing peptide fraction arrays on MALDI targets for proteomic applications. An array-producing microdispenser will be utilized for parallel processing, yielding even higher throughput. MALDI analysis is inherently high- throughput and increasing the sensitivity will drastically increase the output ofproteomic research efforts. PROPOSED COMMERCIAL APPLICATIONS: Proteomic-based research for drug discovery, diagnosing disease and monitoring disease requires massively parallel processing. A high-throughput instrument which is also very sensitive is required for these studies to continue. Our system would be a pioneer in the field and able to capture a significant share of the market.